The development of quantum computers based on spin photons and diamond has the potential to offer significant advantages over other quantum computing technologies, such as lower cooling requirements, longer operating times, and lower error rates. The SPINNING project, coordinated by the Fraunhofer Institute for Applied Solid State Physics IAF, is working on advancing the development of spin-photon-based quantum computers. The consortium recently presented their interim project results at the mid-term meeting of the BMBF funding measure Quantum Computer Demonstration Setups in Berlin.
The goal of quantum computers is to solve complex problems in seconds that would take modern supercomputers decades to compute. However, the path to achieving this goal is still unclear due to several competing approaches to realizing quantum computers, each with its own advantages and disadvantages. The SPINNING project aims to develop a quantum computer based on spin photons and diamond, which is expected to have lower cooling requirements, longer operating times, and lower error rates than other quantum computing approaches. This hybrid concept also offers greater scalability and connectivity for flexible connection with conventional computers.
In the SPINNING project, qubits are created using color centers in the diamond lattice by trapping an electron in artificially created lattice defects doped with nitrogen, silicon, germanium, or tin. These qubits are then used to form a matrix structure called a qubit register, which can be optically coupled over long distances to enable information exchange. The project also involves the development of software and hardware components for controlling the central electron spins and registers, as well as demonstrating the entanglement of qubit registers.
The consortium of the SPINNING project has achieved significant successes in the development of the spin-photon-based quantum computer. They have successfully demonstrated the entanglement of two registers of six qubits each over a distance of 20 m with high fidelity. Improvements have been made in the material processing, color center generation, and photonic resonator technology. The project has also developed the necessary electronics for operating the quantum computer and demonstrated its applications for artificial intelligence.
In comparison with quantum computers based on superconducting Josephson junctions (SJJs), the spin-photon-based quantum computer in the SPINNING project has shown advantages in terms of error rate and coherence time. The development of the project is ongoing, with remaining technical challenges including the further development of resonator design and software for automatic control of the quantum computer’s routing. The project is funded by the BMBF and involves a consortium of universities, research institutions, industrial companies, and associated partners.
Overall, the SPINNING project is making significant progress in advancing the development of spin-photon-based quantum computers based on diamond technology. The project’s achievements in improving error rates, coherence time, and hardware and software components demonstrate the potential for this approach to offer significant advantages over other quantum computing technologies. Continuing advancements in resonator design and software development will be crucial for the success of the project and the future development of quantum computing technology.